This invention relates broadly to the art of urethral drainage catheters, and more particularly to such catheters having valves therein operated from outside of the body.
Discharge of bladder contents can be a source of serious and distressing problems for persons whose natural anatomy is temporarily, or over a longer period of time, incapable of completely controlling the outflow of urine. A traditional urethral balloon catheter of a well known type comprises a flexible tube which extends from outside the body along the urethra into the bladder. More recently, urethral balloon catheter systems have been developed including normally-closed valves in the catheters which can be opened by applying outside forces to the valve to control the flow of urine. Such a valve system is disclosed in U.S. Pat. Nos. 4,350,161 and 4,432,757 to Davis. Although the Davis valved catheter, which is anchored completely inside the urinary tract offers many advantages to persons with impared thinking and/or muscle ability, it is not sufficient in those situations where users thereof cannot apply the necessary external forces to manipulate the valve. Such a situation arises when a person undergoes major surgery, such as open heart surgery, in which he is asleep for a number of hours, and even after waking is usually incoherent. In major-surgery situations, patients are often incontinent for as many as three or four days thereafter and often for the first one or two days after the surgery they are totally incapable of applying forces to activate valves located in urinary tracts In any case it is often desirable to monitor urine production of such patients the first few days after the surgery. Usually, traditional urethral balloon catheters are used in these major surgery situations which allow urine to continuously drain through main lumens into bags located outside the patients. A major disadvantage arising from a drainage lumen extending outside of a body over a period of time is that bacteria spreads along the main lumen into the bladder and ultimately to the kidney In this respect, after only a day of a tube extending from outside of a body into a bladder bacteria has begun to move into the bladder through the tube. One can expect to get an infection if the catheter is left extending outside of the body for four days and frequently such infections are major. One of the purposes of the Davis catheter described in U.S. Pat. Nos. 4,432,757 and 4,350,161 is to avoid a tube which extends outside of the body, therefore allowing the body's natural protective mechanisms operating at the meatus of the urinary tract (such as the fossa navicularis for males which produces antibodies) to prevent bacteria from entering the urinary tract.
Although the Davis catheter of the above-described patents could be used for a patient after one or two days following a major surgery, that is once the patient becomes lucid and active, during the first day after surgery that catheter is not appropriate because it is desirable to continually monitor the flow of urine and the patient is usually not capable of sensing the need for, nor activating the valve for, evacuating urine. For these reasons, the Davis urethral valved catheter described in the above patents, without further improvements, cannot practically be used for such post-surgery patients.
Another shortcoming of the valved catheters of the prior art, such as that described by Davis in U.S. Pat. Nos. 4,432,757 and 3,977,408, is that a clot or some other material passing through a urinary tract might clog the urinary tract, including the valve. Thus, it is an object of this invention to provide a method and apparatus for irregation of the urinary tract to thereby drive clots out of a urinary tract back up into a bladder where they can be dissolved before passing out through the urinary tract.
It is an object of this invention to provide a catheter system and method employing an insertable, urethral catheter which freely drains a patient's bladder but which can also be adjusted to allow selective drainage thereof.
It is a further object of this invention to provide a catheter system and method which has the features of the catheter described in U.S. Pat. Nos. 4,432,757 and 3,977,408 to Davis but which has the added feature of allowing the catheter to be used as a free drainage catheter.
It is a further object of this invention to provide such a catheter system and method which inhibits infection to a much greater degree than do most free-flow urinary catheters.